South-Central Rockies Forests, Part IA: Greater Yellowstone World Heritage Site

Path of the pronghorn, the 1988 fires, and ancient microbes in thermal pools         

The Greater Yellowstone article is divided into three parts. Part A includes the overview, world heritage sites, national historic landmarks, and national natural landmarks. Part B includes national forests, national parks, reservoirs, and national trail system. Part C includes wilderness areas, wildlife refuges, state, and local areas.

The steep, high mountains of the South-Central Rockies are mostly covered with coniferous forests dominated by lodgepole pine, Douglas-fir, subalpine fir, and Engelmann spruce. Foothills are sagebrush and grass-covered. The South-Central Rockies area has been divided into two parts, the eastern portion of which is dominated by the Yellowstone supervolcano and the western portion is dominated by the Idaho batholith. Prominent ranges in the eastern portion of the ecoregion are Gallatin (Gallatin National Forest (NF) and Yellowstone National Park (NP), Gravelly (Beaverhead NF), Madison (Beaverhead and Gallatin NF), Big Belt (Gallatin and Helena NFs), Little Belt (Lewis and Clark NF), Crazy (Gallatin and Lewis and Clark NFs), Absaroka (Gallatin, Custer, and Shoshone NFs and Yellowstone NP), Tobacco Root (Deerlodge and Beaverhead NFs), Teton (Grand Teton NP and Targhee NF), Gros Ventre (Teton NF), Snake River (Caribou NF), Caribou (Caribou NF), and Wyoming Mountains (Bridger and Teton NFs). In the middle of this is the Yellowstone Plateau (Yellowstone NP, Targhee NF, and Gallatin NF), a volcanically active area with world famous geothermal features, and high elevation valleys including Jackson Hole (Grand Teton NP), Star Valley (between Bridger and Caribou NFs), Lamar Valley, Hayden Valley, and Pelican Valley (Yellowstone National Park). Eastern ranges such as the Wind River and Beartooth will be added when map research is expanded to the east of the 110th meridian.

Of the many notable features of the Greater Yellowstone ecosystem is its intact wildlife and large mammal populations. One of the longest remaining wildlife migration corridors in North America begins at the upper Green River valley in Wyoming and heads north through the Bridger and Teton NFs to the National Elk Refuge and Grand Teton NP north of Jackson. Archaeological evidence indicates that this migration of pronghorn has been ongoing for 6,000 years. The pronghorn leave the deep snows of Jackson Hole and head south each fall, returning in the spring. The pronghorn use specially constructed overpasses on US 191 at Trappers Point, Wyoming which reduces the risk of vehicle collisions. There are two overpasses, six underpasses, and eight-foot-high barrier fencing to channel the animals to crossing points. The corridor follows the Green River north to where it comes close to the Gros Ventre River, then follows the Gros Ventre downstream to Jackson Hole.

Between 1995 and 1997, 41 gray wolves were reintroduced to Yellowstone National Park. This population quickly grew and has played a role in reestablishing predator-prey dynamics. As a condition of reestablishment, hunting was allowed outside the park. The hunting has slowed dispersal. There is some concern that hunting of the wolves outside the park when they range more widely in winter will eventually affect their social dynamics and age structure. If the population is skewed toward younger animals, elk predation would likely increase (Morell 2009).

The 1988 summer fires in the Yellowstone ecosystem resulted in extensive forest damage across more than 500,000 ha, affecting 20 separate river basins and burning one third of the national park. This event sparked a debate about the role of fires in wildlands that still occurs today, and subsequent research is Yellowstone’s contribution to the debate about fire management in the West (Stone 1998).  Fires occurred in all areas of the park except the southwestern corner, but were patchy. About 28 percent of the Yellowstone Lake watershed burned. Forest regeneration in the high elevation area is believed to be on a 300-year cycle. Although it was initially thought that controlled burning could have reduced the damage, further research indicates that the prehistoric fire regime in the lodgepole pine forest of Yellowstone is characterized by infrequent, high intensity, stand-replacing fires (Anderson et al. 1999). Despite the devastation, terrestrial and aquatic life recovered quickly with few adverse effects (Minshall, Brock, and Varley 1989). One of the myths debunked after the fires was the belief that forest fires sterilize the soil, limiting subsequent plant succession to grasses and herbs. Contrary to this belief, many areas of the park are now regenerating in lodgepole pine, and even more rapidly than expected. Wildlife, including the elk and bison herds, were only minimally affected.

The post-fire landscape is as patchy and variable as the pre-fire landscape, with areas in all stages of plant succession. This is due to the variable burn densities and hotness of different fire areas. In most areas, the regeneration comes from resprouting survivors and their seeds (Baskin 1999). One species that appeared hurt by the fires was aspen, which grows in large clonal stands. This was believed to be influenced by heavy browsing by elk. More recent research confirms the influence of elk on aspen regeneration. The wolf introduction in the mid-1990s has resulted in a reduction in the elk population, and, perhaps more importantly, the introduction of a fear factor. Because aspen groves provide cover for wolves, elk are too nervous to linger and eat at an aspen grove. Aspen groves have been declining in the park since wolves were eliminated in the 1920s. With the reintroduction of a top predator, they have regenerated. In a parallel trend, willows and cottonwoods have also been regenerating along Yellowstone’s streams, providing streambank stabilization benefits (Morell 2007).

Yellowstone’s famous thermal pools are another unique natural wonder, a legacy of the supervolcano that lies underneath. In 1985, the Taq polymerase enzyme, originally isolated from a Yellowstone National Park hot spring microbe, was used in the polymerase chain reaction DNA fingerprinting process. DNA fingerprinting eventually revolutionized the study of biology; however, no royalties went to the park.  To potentially receive park funding in the future, the National Park Service subsequently has allowed Cooperative Research and Development Agreements to allow scientific exploration of the unique microbes found in the park (Pennisi 1998). There are numerous unusual thermophilic microbes that have been isolated from Obsidian Pool in the Hayden Valley. Some are believed to be living relatives of the earliest life on earth, and are classified in their own kingdom in the Archaea domain (Milstein 1995).

The Teton Range, shared by the Targhee NF and Grand Teton NP, is host to ten glaciers. Edmunds et al. (2012) studied the area loss of three glaciers in the Tetons from 1967 to 2006, finding that losses ranged from 17 to 60 percent, with the greatest loss from the smallest glacier. Volume losses for the three glaciers were estimated at 3.2 million cubic meters. Climatic data indicated a significant increase in temperatures from 1968 to 2006 compared to the previous 1911 to 1967 historical temperatures.

There is one World Heritage Site, which is also a Man and the Biosphere Reserve in the Greater Yellowstone subsection of the South Central Rockies forests. Yellowstone NP, Idaho, Montana, and Wyoming (site 1 on accompanying map), is a land of superlatives–the world’s first national park, the world’s largest concentration of geysers (300), the largest concentration of petrified trees in the world, North America’s largest high altitude lake, and a supervolcano. While the park is primarily an intact wildland, complete with predators and prey, there are also national  historic landmarks (NHLs)and archaeological sites.  Fort Yellowstone, Fishing Bridge Museum, Madison Museum, Norris Museum, Northeast Entrance Station, Obsidian Cliff, and Old Faithful Inns are NHLs. The park is also part of the World Network of Biosphere Reserves. The Lewis River and Snake River in the southern part of the park are part of the National Wild and Scenic Rivers system. The Morning Glory, South Rim, and Three Senses National Recreation Trails (NRTs), described under National Trail System, are within the park. The list of natural wonders is large.  The following is a minimal list of the important sites:

  • Black Canyon of the Yellowstone (N45˚1’ W110˚37’) is reached from a trail that starts in Gardiner and follows the river upstream along the Gallatin NF-Yellowstone NP boundary.
  • Calcite Springs (N44˚54’ W110˚24’) are thermal springs at the foot of basalt cliffs.
  • Firehole Falls (N44˚38’ W110˚52’) are south of Madison Junction.
  • Fountain Paint Pot and Firehole Lake Drive (Lower Geyser Basin) (N44˚33’ W110˚48’) is on the Grand Loop Road south of the West Entrance Road.
  • Gallatin Petrified Forest in the northwest corner of the park extends north into the Gallatin NF.
  • Gardner River Canyon (N45˚0’ W110˚42’) is along the North Entrance Road.
  • Gibbon Falls (N44˚39’ W110˚46’) is an 86-foot waterfall on the Yellowstone caldera rim.
  • Grand Canyon of the Yellowstone extends from the upper and lower falls at Canyon Village (N44˚43’ W110˚30’) to the Tower Fall area (N44˚54’ W110˚23’); Tower Falls are 132 feet in height.
  • Heart Lake Geyser Basin (N44˚17’ W110˚30’) is several miles to the east of the South Entrance Road.
  • Isa Lake (N44˚26’ W110˚43’), on the Grand Loop Road between Old Faithful and West Thumb, is on the Continental Divide and drains to both the Atlantic and Pacific Oceans.
  • Lone Star Geyser (N44˚25’ W110˚48’) is five miles south of Old Faithful.
  • Midway Geyser Basin (N44˚31’ W110˚50’)  is on the Grand Loop Road south of the Lower Geyser Basin; there is a constant discharge of 40,000 gallons per minute to the Firehole River from springs here. The largest spring is Grand Prismatic Spring.
  • Mud Volcano (N44˚38’ W110˚26’) along the Yellowstone River on the Grand Loop is a huge seething mudpot. Nearby is the Grumper, Sour Lake, and Sulphur Caldron. This is an area where rare thermophilic microbes have been studied in Obsidian Pool. Sulphur Caldron is an acidic spring with a pH of 1.3.
  • Natural Bridge (N44˚32’ W110˚27’) is along the Grand Loop Road on the west side of Yellowstone Lake.
  • Norris Geyser Basin (N44˚44’ W110˚42’) on the Grand Loop Road south of Mammoth  includes One Hundred Springs Plain.
  • Old Faithful (Upper Geyser Basin) (N44˚28’ W110˚50’) is on the Grand Loop Road south of the Midway Geyser Basin.
  • Shoshone Geyser Basin (N44˚21’ W110˚48’) is accessible via a 12-mile trail from Old Faithful and is on the western edge of Shoshone Lake.
  • Specimen Ridge (N44˚51’ W110˚14’) is on the Northeast Entrance Road contains the largest concentration of petrified trees in the world, along with leaf impressions and needles.
  • Terrace Springs (N44˚39’ W110˚51’) are at Madison Junction .
  • West Thumb Geyser Basin (N44˚25’ W110˚34’) is on the West Thumb embayment of Yellowstone Lake where the Grand Loop Road junctions with the South Entrance Road.

There are seven National Historic Landmarks in Greater Yellowstone subsection of the South-Central  Rockies forests ecoregion. Fort Yellowstone Historic District, Yellowstone NP, Idaho-Montana-Wyoming , consists of eight sites containing 44 structures associated with the Army administration of Yellowstone NP from 1886 to 1918. At the invitation of the Secretary of the Interior, the US Calvary established a 30-year presence at the then-lawless Yellowstone NP, protecting the park from poachers, souvenir hunters, and tourist developments. Through its protective administration of Yellowstone in its early years, the army is credited with saving the national system of parks and setting the stage for the professional park ranger corps that was implemented by the National Park Service when it was established. The Army introduced backcountry patrols, developed roads and bridges using alignments that did not interfere with natural features, protected wildlife, prohibited domestic animals, preserved features from development by prohibiting elevators at waterfalls, prohibited railroads, fought forest fires, and prevented timber harvest. These principles of conservation and stewardship were later adopted for the entire park system.

The core of the historic district, and the location of most of the buildings, is at Fort Yellowstone (site 2), Wyoming (N44˚59’ W110˚42’), also known as Mammoth Hot Springs, located on the Grand Loop Road south of Gardiner, Montana.  This was the headquarters for military administration of the park and contains standard calvary barracks that would have been constructed in the late 19th century.  The other sites in the NNL are:

  • Fort Yellowstone Powerhouse, Wyoming (N44˚57’ W110˚42’)
  • Fort Yellowstone Cemetery, Wyoming (N44˚58’ W110˚42’)
  • Roosevelt Arch, Gardiner, Montana (N45˚2’ W110˚43’), located at the north entrance.
  • Norris Soldier Station (site 3), Norris Junction, Wyoming (N44˚44’ W110˚42’), located off the Norris Canyon Road; today the facility has been rebuilt to original specifications and houses the Museum of the National Park Ranger
  • Bechler River Soldier Station (site 4), Wyoming (N44˚9’ W111˚3’), in the southwest corner of the park
  • Buffalo Lake Snowshoe Cabin (site 5), Idaho (N44˚20’ W111˚5’), located on Boundary Creek Trail in the southwest corner of the park

Jackson Lake Lodge (site 6), Grand Teton NP, Wyoming (N43˚53’ W110˚35’), is located on US 89-191-287 on the east side of Jackson Lake. In 1927, John D. Rockefeller began purchasing land in Jackson Hole to preserve the Grand Teton viewshed. This ultimately resulted in the expansion of the Grand Teton National Park to include Jackson Hole in 1950. The 1955 hotel is constructed on a terrace overlooking Jackson Lake and the Grand Tetons. It includes a large two-story glass window to provide dramatic views. The lodge itself was the design precursor for the National Park Service Mission 66 program to ready the park system for increased visitation in the postwar years. Designed and financed by Rockefeller, the lodge was intended to be a pilot project for future park service facilities. There are 38 contributing buildings to the NNL, including a cottage community.

Murie Ranch Historic District (site 7), Grand Teton NP, Wyoming, (N43˚39’ W110˚44’), commemorates the retreat operated by Olaus, Adolph, Margaret, and Louise Murie, important figures in the American conservation movement from the 1930s through 1980s. Olaus and Adolph were federal scientists in the 1920s, studying grizzlies, wolves, elk, and coyotes in Alaska and Jackson Hole and emphasizing the ecological context and holistic relationships in natural systems. Later the family also made the transition to the popular conservation movement, and became prolific writers for the magazines of the National Audubon Society, Wilderness Society, and National Parks Conservation Association. Olaus became director of the Wilderness Society and ran the society at least partly out of the ranch. The log cabins on the Snake River became a Mecca for the American conservation movement in the post-war years. The Muries were involved in the Arctic National Wildlife Refuge establishment, the opposition to the Echo Park Dam in the Dinosaur National Monument, and the promotion of the Wilderness Act. Margaret Murie was on the governing council of the Wilderness Society and was influential in the passage of the Alaska National Interest Lands Conservation Act in 1980. The historic district includes about 30 buildings just south of the Moose headquarters and visitor center. Today the Murie Center holds conservation education programs in the historic district and promotes science-based wilderness and wildlife conservation.

Norris, Madison, and Fishing Bridge Museums, Yellowstone NP, Wyoming, are three remaining trailside museums along the Yellowstone Grand Loop Road. They are the best remaining structures of rustic design in the park system. They served as models for hundreds of other buildings built during the 1930s in national, state, and local parks. The idea was that visitors would receive orientation to the resources of the area. The architect, Herbert Maier, believed that museums should interpret and guide visitors rather than be a passive repository of exhibits. Architecturally, the museums had enormous peeled logs, natural boulders, outside observation terraces, and tree wells. Originally, there was a fourth trailside museum at Old Faithful, but that was demolished in 1971.

The Norris Geyser Basin Museum (1929, site 8) (N44˚44’ W110˚42’) was a dramatic entrance to the Norris Geyser Basin. An open air foyer with a gable roof is in the center of the building. Today it is used as a bookstore near a modern museum. The Madison Information Station (1929, site 9) (N44˚39’ W110˚52’), is a T-shaped building adjacent to the confluence of the Madison and Gibbon Rivers. It is still in use. The Fishing Bridge Museum and Visitor Center (1930-1931, site 10) (N44˚34’ W110˚23’), is also still in use and is a stone, log, and concrete structure built using massive boulders up to five feet in diameter for walls. The building seems to rise out of a rock outcrop. Terraces with low stone walls surround the museum. There is an adjacent amphitheater, and the terrace overlooks Yellowstone Lake.

Northeast Entrance Station (site 11),Yellowstone NP, Montana (N45˚0’ W110˚1’), was built in 1935 on present-day U.S. Route 212. This log structure of classic rustic design set the trend for subsequent national park construction and was used as a model in the 1935 guidebook on park structures and facilities. The property consists of the entrance station and adjoining ranger residence and ranger station.

Obsidian Cliff  (site 12), Yellowstone NP, Wyoming (N44˚49’ W110˚44’)  is located on the Grand Loop Road 13 miles south of Mammoth Hot Springs and just north of Beaver Lake. The dark volcanic glass found in Yellowstone was highly prized and extensively traded in prehistoric times to locations as far away as Ohio and Michigan. For the past 12,000 years, the site has been quarried, with as much as 91 percent of the obsidian found in archaeological sites in the western US coming from the park. The cliff itself is 200 feet high and one-half mile long. Nearby Obsidian Cliff Kiosk (1931) was one of the first wayside exhibits in the National Park System.

Old Faithful Inn (site 13), Yellowstone NP, Wyoming (N44˚28’ W110˚50’), one of the most famous hotels in the world, is located on the Grand Loop Road overlooking Old Faithful Geyser. Constructed in 1904 and one of the best examples of rustic resort architecture, it is still in use, offering 329 rooms, and believed to be one of the largest log buildings in the world, at 700 feet in length. A seven-story lobby has a large stone fireplace.

Rankin Ranch (site 14), William D. Rankin estate, adjacent to Helena National Forest, Montana (N46˚38’ W111˚34’), was the family home of Jeanette Rankin, the first woman elected to the U.S. House of Representatives. She spent her summers at this ranch east of today’s Canyon Ferry Lake on the edge of the Big Belt Mountains. Rankin was a lifelong advocate for women’s suffrage. She was the first woman in the world elected to a national representative body. She was elected at a time when most states did not allow women to vote, although Montana did. She served one term in 1917-1919 and another in 1941-1943. This famously put her in a position to vote against entering both world wars. She was the only representative to vote against the declaration of war on Japan. This ranch, located on Forest Highway 359 along Avalanche Gulch on the east side of Canyon Ferry Lake, was her summer home from 1923 to 1956.

There are three National Natural Landmarks in the Greater Yellowstone subsection of the South Central  Rockies forests ecoregion. Big Springs (site 15), Targhee National Forest, Idaho (N44˚30’ W111˚15’) is just west of Yellowstone NP where Idaho, Montana and Wyoming come together. It is the only first magnitude spring (120 million gallons per day) issuing from lava flows and is the source of the South Fork of Henry’s Fork River. There is a campground adjacent to the spring, which is noted for enormous rainbow trout.

Middle Fork (Sixteenmile Creek) Canyon, (site 16), Gallatin NF and private lands, Montana (N46˚7’ W110˚58’), is an outstanding example of a canyon cut across the grain of the geologic structure by a superposed stream. In this case, the Middle Fork Sixteenmile Creek cuts across the Elkhorn Ridge in the Bridger Range. Only a small portion of the canyon on the east side is within national forest lands. Sixteenmile Road between Ringling and Maudlow traverses the canyon.

Two Ocean Pass (site 17), Teton Wilderness, Wyoming (N44˚2’ W110˚10’), is where North Two Ocean Creek begins above the pass and splits into two streams, one that heads toward the Atlantic Ocean and one to the Pacific.


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